Some court filing costs may be in the hundreds of dollars. Box 1: Print the county in which you are filing your petition.See "Where do I. File?" in the Introduction for more information about what county you. This purpose of this packet is to provide you with the information and documents you may need to start or respond to child custody actions. This video from Summit Legal Aid, formerly Laurel Legal Services. Provides line-by-line instructions on how to complete a Custody Complaint form. Fill in a brief statement describing why you want the order changed and how you want the order changed. LINES.